Balancing toys are well known in the art. U.S. Pat. No. 2,458,306 discloses a toy comprising a hemisphere the equatorial section of which forms a flat plain upon which the player attempts to balance blocks.
U.S. Pat. No. 3,241,833 discloses a balancing game comprising a table shaped article and numerous chair shaped article to be balanced one upon the other.
U.S. Pat. No. 3,559,989 discloses a game similar to that of U.S. Pat. No. 2,458,306 except that the toy is floated in water.
U.S. Pat. No. 3,567,221 discloses a toy which comprises a board having a centrally located fulcrum integral with the board at its bottom; the board being balance on the fulcrum when a set of weights are evenly distributed on each side of the board.
U.S. Pat. No. 3,614,106 discloses a balance toy comprising a base and a multiplicity of pieces to be balance one above the other. Each play piece has a pair of outwardly extending arms adapted to hold a weight. The weights must be positioned on the arms so as to cause the play piece to be balanced.
U.S. Pat. No. 3,863,918 discloses a balance toy comprising building blocks of various shapes. The object of the game is to stack the blocks one upon the other in an attempt to reach a maximum height.
U.S. Pat. No. 4,589,664 discloses a balancing toy which comprises a board with a central pair of axes provided with a fulcrum and locations for playing pieces on either side of the axes which fall within rows parallel to the axes. Play pieces of different weights are provided to fit in particular locations on each side of the board. The fulcrum is elevated to allow tilting of the board. The game commences with all weights on the board. Opposing players shift the weights to cause the board to tilt in the direction of the opponent.